Improvement in latch-locks



NITED STATES PATENT OEEICE.

DANIEL K. MILLER, 0E PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT lN LATCH-LOCKS.

Specification forming part of Letters Patent No. 180,255, dated July 25,1876; application filed December 11, 1875.

To all whom it may concern.- l

Be it known that I, DANIEL K. MILLER, of Philadelphia, Pennsylvania, have invented certain Improvements in Locks, of which the following is a specification: l

The objects of-Iny invention are, tirst, t o so construct a lock that it can be applied to doors, Ste., of different thicknesses; and, second, to increase the diculty of picking the lock by instruments inserted through the keyhole. These objects I attain in a manner which I will now proceed to describe, reference being had to the accompanying drawings7 in which- Figures l and 2 are longitudinal sectional views, showing the interior of the lock-case and the mechanism for locking the bolt` in either of its extreme positions; Fig. 3, a transverse section on the line 1 2, Fig. 1; Fig. 4, a transverse section on the line-8 4, Fig. 1; Fig. 5, a sectional plan on the line 5 6, Fig. 4; Figs.' 6, 7, and 8, transverse sections on the lines 7 8, 9 10, and l1 12, Fig. 4, respectively;

.and Figs. 9, 10, 11, and 12, sectional views illustrating modications of my invention.

The face-plate A of the lock is secured to i the body of the door in any suitable manner,

and is provided nearone end with a tubular projection, a, and within the latter lits snugly a tubular sleeve, B, which can be moved longitudinally to and fro within the said projection a, and can be secured in any desired position, as hereafter described, so that the dis- -tance between the plate A and the rim c of the sleeve B can be increased or diminishedv to suit doors of different thicknesses.

Within the sleeve B lits snugly, but so as` to turn freely, the cylinder D, which carries the working parts `of the lock, as described hereafter, and' has at its inner end a square stein, b, fitting into an opening of corresponding shape in a disk, d, which turns in a bearend will project into a recess on either side of a projection, g, on the face of the bolt, the longitudinal move-ment of the latter in such case being prevented. Against the rear of the plate f presses a spring, It, which forces the lsaid plate against a pin, t, the latter engaging with one or the other ot' two concave recesses formed on the said face, and serving to retain the plate in an elevated or depressed condition, as will be readily understood.

The manner of securing the sleeve B to the lprojection a ot' the plate A is shown in Figs. 4 and 6, on reference to which it will be observed that the inner end of the sleeve is slotted t'or a short distance from the end, and to the interior ot' the sleeve, at this slotted portion, is adapted a split ring, j, which' canbe expanded by meansy of a taper screw, la.

In tting the lock to a door the plate A is lirst secured to the inside of the same, the projection a extending intovan opening formed in the door. The slotted end of the sleeve B is then inserted from the outside into the centrai opening of the projection a, and forced` inward until the'rirn. c bears against the outside of the door. The split ringj is then inserted to its place in the slotted end'ot` the sleeve, pressed up against the end of the cylinder D, and its taper screw k turned until the said slotted end of the sleeve has been expanded sufficiently to cause it to bear tightly against the inside of the projection a, when any movementot the sleeve is eectually prevented.

rEhe working parts of the -lock are carried y by the cylinder D, and consist of a series of spring-tumblcrs, m, each having the usual false notches and one deep. notch, and arranged to be moved by the key l, so as' to bripgpthe deep notches'in line.

In a'transverse opening in the cylinder D slides a dog, H, slotted for the reception of thel tumblers m, and provided with a projection, n, Fig. 13, adapted to the deep notches of the tumblers, the ends of the dog H being adapted to recesses o o formed yin the interior of the tubular sleeve B.

When the'deep notches of the tumblers are not in line the dog H cannot slide,4 except to the limited eXtent allowed by the false notches, so that the cylinder` D cannot be turned,

owing to the fact that one end of the immovable dog comes in contact with the end-of the slot o. When the deep notches are brought into line, however, the cam-like end of the notch o will,upon the rotation ofthe cylinder, so act upon the end of the dog that the latter will slide inward, its projection n entering the dcep'notches ot' the tumblers, and its opposite inder has been restored to its normal condi` tion.

1t will bc observed, on referring to Figs. 7 and 8, that the recesses o and o are so arranged that a little lost motion is allowed the 'cylinder D before the dog can be caused to press upon the tumblers, but that the recess p is such that it commences to act on the bolt r the instant the cylinder commences to turn.

It will thus be seen that when the key-hole is unobstructed the tumblers are entirely free from the pressure ofthe dog, so that the insertion 4of an instrument for picking the lock by feeling77 the tumblers is rendered of no account, as this plan is only effective when the dog presses upon the tumblers, and when this is the case in my improved lock the keyhole is obstructed by the bolt i", and in addition to this the movement of the tumblers is prevented, owing to the fact that the dog projects into the false notches of the same.

In Figs. 9, 10, and 1l my invention is shown as applied to a lock in which two sets of tu mblers and a double key are used, a duplex dog, H, adapted to notches in both sets ot'- tumblers, and sliding bolts fr being also used in this case.

In the modification, Fig. 12, the key-hole is 3. The combination of the cylinder D and its sliding bolt r with the sleeve B and its recess p. j

4. rlhe combination of the sliding dog H and sliding bolt i', carried by the cylinder D, with the recesses o, o', and 19 in the sleeve B, said recesses being arranged, in respect to each other, as set forth.

5. The combination of the face-plate A of the lock and its tubular projection a with the slotted sleeve B and its expanding-ring j, as and for the purpose set forth.

In testimony whereof I have signed my naine to this specification in the presence of two subscribing Witnesses.

DANIEL K. MILLER. Witnesses:

HARRY HoWsoN, Jr., HARRY SMITH. 

